Waves in thin oceans on oblate neutron stars
| Autor: | Anna L. Watts, Bart F. A. van Baal, F. R. N. Chambers |
|---|---|
| Přispěvatelé: | API Other Research (FNWI), High Energy Astrophys. & Astropart. Phys (API, FNWI) |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
High Energy Astrophysical Phenomena (astro-ph.HE)
Surface (mathematics) Physics 010504 meteorology & atmospheric sciences FOS: Physical sciences Astronomy and Astrophysics Radius Gravitational acceleration 01 natural sciences Computational physics Neutron star 13. Climate action Space and Planetary Science 0103 physical sciences Oblate spheroid Physics::Space Physics Polar Wave vector Astrophysics::Earth and Planetary Astrophysics Variation (astronomy) Astrophysics - High Energy Astrophysical Phenomena 010303 astronomy & astrophysics 0105 earth and related environmental sciences |
| Zdroj: | Monthly Notices of the Royal Astronomical Society Monthly Notices of the Royal Astronomical Society, 496(2), 2098-2106. Oxford University Press |
| ISSN: | 1365-2966 0035-8711 |
| Popis: | Waves in thin fluid layers are important in various stellar and planetary problems. Due to rapid rotation such systems will become oblate, with a latitudinal variation in the gravitational acceleration across the surface of the object. In the case of accreting neutron stars, rapid rotation could lead to a polar radius smaller than the equatorial radius by a factor $\sim 0.8$. We investigate how the oblateness and a changing gravitational acceleration affect different hydrodynamic modes that exist in such fluid layers through analytic approximations and numerical calculations. The wave vectors of $g$-modes and Yanai modes increase for more oblate systems compared to spherical counterparts, although the impact of variations in the changing gravitational acceleration is effectively negligible. We find that for increased oblateness, Kelvin modes show less equatorial confinement and little change in their wave vector. For $r$-modes, we find that for more oblate systems the wave vector decreases. The exact manner of these changes for the $r$-modes depends on the model for the gravitational acceleration across the surface. 10 pages, 8 figures Accepted for publication in MNRAS |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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